Buffing and polishing

General Composites Discussions Composites Talk
#1

Ok I admit first of not knowing things and I thought I found the easiest way to wet sand and buff a part but after seeing a picture online I may be thinking differently.

I have been using an electric da buffer the Makita that auto geek sells for over a year now. I switched from a random orbital porter cable which was horrible.

It’s a great polisher but it’s huge. It’s uncontrollable with 1 hand and I find myself holding parts with my elbows and knees half the time trying to control them since most the stuff I can’t make a jig and bolt it down…

I thought of just attaching it upside down with some 2x4’s and just using it but I saw a photo of I think someone using a bench polisher for items???

I’ve never used one but they look good. My question is does it make things that much easier and also I only see the layered cloth attachments. Are they good enough to polish out 2000 grit scratches? Any advice is greatly appreciated guys!

#2

New here, but not new to laborious polishing and the desire to figure out quick ways.

I love my porter cable ROS, and use it alot with 3000 grit Trizact discs, but the trick is to slow down the sander. Mine is variable speed, so yours might not be.

The trizact discs cut 1000 grit scratches real fast, and you can follow up directly with medium cut polishing compound, followed by final machine glaze for the wet look.

If looking into a bench buffer for hand held parts, that is an awesome way to go. I bought a small Foredom direct drive dual wheel buffer for dry compound. Plastic compound cuts well past 1000 grit, right to gloss, and follow with machine glaze (I use 3M Perfect It). White rouge is also very versatile.

#3

Awesome tips.

Do you ever get fish tails with your da sander? I was using my 5 inch sander and was wetting things down but upon the surface drying I noticed a lot of fish tails. Was my sandpaper or water dirty or was I trying to sand at to high of speed? Thi was with I think 1500 Amazon.com disks

I haven’t use the 3m trizart ones yet because they are real pricey and I think only come in 6 inch.

#4

Oh yeah, the infamous “drag” - What I call them. Its when the cutting and rubbing action melts a chunk, forms it into a tiny nib that sticks to the disk, then grinds a trough in to the polished surface. Sometimes its just a random pc of foreign dust. This is why buffing needs insanely clean buffing areas. I tell my workers to pre-clean all buffing and sand pads prior to use. Use lots of water, but still a good chance of “drags”.

This is precicely where the structured abrasives like Trizact come in. They have micro grooves formed into the silicon carbide that primarily are there to irrigate water away to prevent hydroplaning, allowing good constant cutting. But the other benefit is that it irrigates all the dust nibs away as well. I was amazed how clean the surface was - free of all deep drags. Norton also makes discs like this.

#5

I agree with using the Trizact discs. Yes they are very expensive but I find in the big picture they pay off. A proper da sander is important too.

#6

I hate it when you guys are right. Now I must by these pads! Haha thanks